From: Victor Kamensky <victor.kamensky@linaro.org>
Date: Thu, 12 Jun 2014 16:30:05 +0000 (-0700)
Subject: ARM: KVM: MMIO support BE host running LE code
X-Git-Tag: firefly_0821_release~3680^2~36^2~16^2^2~79
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=d6ff09058017a8dfd96fa24502691c83df6566e7;p=firefly-linux-kernel-4.4.55.git

ARM: KVM: MMIO support BE host running LE code

In case of status register E bit is not set (LE mode) and host runs in
BE mode we need byteswap data, so read/write is emulated correctly.

Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
(cherry picked from commit 27f194fd360a96cc64bebb2d69dd5abd67984b8a)
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---

diff --git a/arch/arm/include/asm/kvm_emulate.h b/arch/arm/include/asm/kvm_emulate.h
index 0fa90c962ac8..69b746955fca 100644
--- a/arch/arm/include/asm/kvm_emulate.h
+++ b/arch/arm/include/asm/kvm_emulate.h
@@ -185,9 +185,16 @@ static inline unsigned long vcpu_data_guest_to_host(struct kvm_vcpu *vcpu,
 		default:
 			return be32_to_cpu(data);
 		}
+	} else {
+		switch (len) {
+		case 1:
+			return data & 0xff;
+		case 2:
+			return le16_to_cpu(data & 0xffff);
+		default:
+			return le32_to_cpu(data);
+		}
 	}
-
-	return data;		/* Leave LE untouched */
 }
 
 static inline unsigned long vcpu_data_host_to_guest(struct kvm_vcpu *vcpu,
@@ -203,9 +210,16 @@ static inline unsigned long vcpu_data_host_to_guest(struct kvm_vcpu *vcpu,
 		default:
 			return cpu_to_be32(data);
 		}
+	} else {
+		switch (len) {
+		case 1:
+			return data & 0xff;
+		case 2:
+			return cpu_to_le16(data & 0xffff);
+		default:
+			return cpu_to_le32(data);
+		}
 	}
-
-	return data;		/* Leave LE untouched */
 }
 
 #endif /* __ARM_KVM_EMULATE_H__ */